Shadow black leather Portofino low-top leather sneakers from Koio featuring round toe, front lace-up fastening, branded heel counter and flat rubber sole. POSITIVELY CONSCIOUS: This Planet Conscious product is crafted with leather that has been produced in an audited and certified Leather Working Group (LWG) tannery — scored according to a three-tier system. The LWG assesses and certifies leather manufacturers that reduce the environmental impact of production..